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| author | Kartik Agaram <vc@akkartik.com> | 2020-12-29 21:16:28 -0800 |
|---|---|---|
| committer | Kartik Agaram <vc@akkartik.com> | 2020-12-29 21:17:03 -0800 |
| commit | 520e3c25427f48bd68ded41a5678ca43c28a9891 (patch) | |
| tree | 3d8cfde1f031e4f4c856bb42ac3c370a1a08d55d /baremetal/101screen.subx | |
| parent | 0daf12c59aa8a6b9d996f56797b6f74c3aa0a738 (diff) | |
| download | mu-520e3c25427f48bd68ded41a5678ca43c28a9891.tar.gz | |
7470
The ol' 8-byte-register-names issue strikes again. There's no way to access the lower 8 bits of ESI. There's still a bug in baremetal/ex2.mu; it's printing transposed somehow.
Diffstat (limited to 'baremetal/101screen.subx')
| -rw-r--r-- | baremetal/101screen.subx | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/baremetal/101screen.subx b/baremetal/101screen.subx index 3e98d96b..fb87709c 100644 --- a/baremetal/101screen.subx +++ b/baremetal/101screen.subx @@ -6,10 +6,10 @@ pixel: # screen: (addr screen), x: int, y: int, color: int 89/<- %ebp 4/r32/esp # . save registers 50/push-eax - 56/push-esi - # esi = screen - 8b/-> *(ebp+8) 6/r32/esi - 81 7/subop/compare %esi 0/imm32 + 51/push-ecx + # ecx = screen + 8b/-> *(ebp+8) 1/r32/ecx + 81 7/subop/compare %ecx 0/imm32 { 75/jump-if-!= break/disp8 # bounds checks @@ -30,15 +30,15 @@ pixel: # screen: (addr screen), x: int, y: int, color: int # eax += location of frame buffer 03/add-> *0x7f28 0/r32/eax # *eax = color - 8b/-> *(ebp+0x14) 6/r32/esi - 88/byte<- *eax 6/r32/esi + 8b/-> *(ebp+0x14) 1/r32/ecx + 88/byte<- *eax 1/r32/CL # return eb $pixel:end/disp8 } # TODO: fake screen $pixel:end: # . restore registers - 5e/pop-to-esi + 59/pop-to-ecx 58/pop-to-eax # . epilogue 89/<- %esp 5/r32/ebp |